The he OS1-FL from Opti-Sciences offers a powerful combination of sophisticated measurement capability and ease of use in a low-cost package.

Measures Dark & Light Adapted Parameters: Y, Fv/ Fm, Fs, Fms, Fo, Fm, etc.
Non-Destructive Measurement
Lightweight, Hand-Held Design Optimized for Field Work
Accurate, Reliable, and Easily Repeatable Measurements
Internal Data-Logging
Stand Alone Operation- No P.C. Required